Because “Travel Ban 3.0” differs in some key respects from Ban 2.0, the justices canceled the oral argument originally scheduled for next week and directed the parties to file short briefs addressing the question of whether the case is now moot. Those briefs are due today.

A case is moot when the underlying issues no longer present a live controversy. We can expect the plaintiffs (respondents in the Supreme Court) to argue that the challenge to the administration policy is not moot, because Travel Ban 3.0 has the same basic flaws as Ban 2.0.

We can expect the government (petitioner in the Supreme Court) to argue that the challenge is moot both on technical grounds—the earlier policy has expired—and as a substantive matter because of substantial differences between versions 3.0 and 2.0.

International travelers arrive on the first day of the the partial reinstatement of the Trump travel ban, temporarily barring travelers from six Muslim-majority nations from entering the U.S., at Los Angeles International Airport (LAX) on June 29, 2017 in Los Angeles, California. Under a Supreme Court order, foreigners who do not have a so-called 'bona fide relationship' with a person or entity in the United States can be banned. The ban effects travelers from Iran, Libya, Somalia, Sudan, Syria and Yemen. David McNew/Getty

Or perhaps one or more parties will take an unexpected position on mootness. In any event, precedents concerning mootness are complex, technical, and somewhat internally inconsistent, because the justices sometimes distort the mootness doctrine to avoid issues they want to duck or to hear cases they want to resolve. Whether Ban 3.0 is sufficiently different from Ban 2.0 to warrant a finding of mootness will thus turn on a combination of technical, substantive, and prudential factors.

However the Court resolves the mootness issue, the challenges to the Trump policy will not simply go away. Either the Supreme Court itself will restore the case to its calendar or the plaintiffs will return to the lower courts to amend their earlier findings or initiate new legal challenges.

The Key Differences

Travel Ban 3.0 differs from version 2.0 in a number of respects. The earlier version was a 90-day ban on entry into the US by nationals of six majority-Muslim countries: Iran, Libya, Somalia, Sudan, Syria, and Yemen. The stated purpose of the 90-day ban was to allow the government to conduct a review of its own screening policies and the screening policies of other countries in order to ensure that persons entering the country did not pose a substantial risk of engaging in terrorism.

The 90-day period has expired, and the government has completed its review. That review concluded that only one country on the list—Sudan—was providing reliable information and was therefore removed from it.

The proclamation also adds Chad and North Korea to the list, while banning travel by government officials from Venezuela. Iraqis were subject to Ban 1.0 and removed from Ban 2.0. Ban 3.0 does not ban travel to the US by Iraqis but subjects them to heightened screening.

Unlike Ban 2.0, which was temporary, Ban 3.0 has no expiration date. However, that is somewhat misleading. The proclamation itself sets forth criteria for the suspension of immigration and other forms of travel from the affected countries. It also describes Chad, Iraq, and Libya as valuable partners in fighting terrorism but nonetheless notes the inadequacy of the information they are currently able to provide.

Thus, one would expect that if the capacity of a cooperative country improves or an uncooperative country becomes cooperative it would be removed from the list by a future proclamation.

In addition to its ban on travel by nationals of the listed countries, Ban 2.0 also capped refugee admissions at 50,000 and suspended entry into the US of all refugees for a period of 120 days. The 120-day period will expire on October 23 and, accordingly, the letter briefs that will be filed today will address whether it is about to become moot. With the oral argument having been taken off the calendar, it is virtually impossible for the Court to adjudicate the refugee suspension before October 23.

Meanwhile, the administration has yet to issue a superseding proclamation or executive order with respect to refugees, although last week it was reported that the administration planned to lower the annual cap to 45,000, substantially down from the 110,000 approved in the last year of the Obama administration.

Whether in the cases currently before the Supreme Court or in amended or new challenges to be filed in the lower courts, will Ban 3.0 fare better than did Ban 2.0?

The lower courts found two sorts of flaws in Ban 2.0. The US Court of Appeals for the Ninth Circuit held that the ban exceeded the president’s statutory authority, while the US Court of Appeals for the Fourth Circuit found that it discriminated against Muslims on the basis of religion in violation of the First Amendment’s Establishment Clause.

Statutory Authority

Travel Bans 1.0 and 2.0 invoked authority delegated to the president by Congress to bar entry into the US of “any class of aliens” “whenever the President finds” that their entry “would be detrimental to the interests of the United States.” The Ninth Circuit invalidated Travel Ban 2.0 on the ground that the president had made no findings based on evidence to support the conclusion that the 180 million people subject to the order pose a security risk.

The court also rejected the government’s contention that a pause to improve vetting counted as a finding of risk, especially in light of the absence of any evidence that existing vetting procedures are inadequate.

Travel Ban 3.0 invokes the same statutory authority as its predecessors but with a potentially critical difference. The proclamation states that the new ban is based on a global review of vetting procedures and information sharing.

Will that make a difference? Maybe, but even Travel Ban 3.0 exhibits a flaw that concerned the Ninth Circuit: The government fails to connect nationality-based risk to country of origin. That flaw can be illustrated by considering a concrete case.

Suppose that a Libyan national has been living and working as a history professor in Canada for the last ten years.

Why should the fact that (1) the Libyan government is currently unable to fully verify the identities of people currently in Libya or (2) Libya became a locus of terrorism long after the history professor moved to Canada bear on the risk that she poses or (much more likely) does not pose, when the US government can get all of the information it needs from Canada.

Perhaps the government will be able to argue that the authority to grant exceptions to the Ban suffices for such cases, but that argument was available with respect to Ban 2.0 and yet the Ninth Circuit found it insufficient anyway. Accordingly, if the Ninth Circuit were to apply to Ban 3.0 the same test it applied to Ban 2.0, the new ban would also likely fail for lack of statutory authority.

Meanwhile, however, the government’s brief challenging the Ninth Circuit ruling with respect to Ban 2.0 (which was filed before the superseding proclamation) sets forth arguments that, if accepted, would even more clearly lead to a decision upholding Ban 3.0.

Most fundamentally, the government argues that the president need not offer any particular justification for a finding that admission of a class of aliens would be detrimental; he only needs to make the finding; and, the government says he clearly did so in Travel Ban 2.0. He also did so in the proclamation announcing Ban 3.0.

Thus, although it is possible that some judges or justices who might have been inclined to invalidate Ban 2.0 as beyond the president’s statutory authority would now be inclined to find Ban 3.0 lies within his authority, the arguments of the parties would not appear to change significantly in light of the proclamation.

Anti-Muslim Animus

What about the discrimination claim? Both Bans 1.0 and 2.0 applied exclusively to nationals of Muslim-majority countries. Indeed, Ban 1.0 contained a special provision that would have given preferences to Christian refugees over Muslim ones (at least in operation and likely by design, though not by the explicit language of the executive order).

By contrast, Ban 3.0 applies to six majority-Muslim countries but also to one country (Venezuela) in which Muslims make up less than half of one percent of the population and another (North Korea) with virtually no Muslims at all. Should that make a difference?

Probably not. For one thing, Venezuelan nationals are not subject to the same ban as nationals of the other listed countries. The proclamation limits travel by Venezuelan government officials, but that appears to be a response to the repressive policies of the Venezuelan president Nicolás Maduro rather than a response to any terrorist threat from Venezuela.

North Korea is a hostile country whose nationals could pose a threat to the US, but even prior to the proclamation there was virtually no travel from North Korea to the US, except by diplomats heading to the United Nations.

Neither the addition of North Korea and government officials from Venezuela nor the substitution of one majority-Muslim country (Chad) for another (Sudan) much changes the bottom line. Ban 3.0 has roughly the same grossly disproportionate impact on Muslims that Bans 1.0 and 2.0 had.

The proclamation could nonetheless be a game-changer for the discrimination claims, because, on its face, it cites a plausible national security justification for the selection of the particular countries. Whether that justification will survive further litigation depends on two questions.

First, will the courts regard Ban 3.0 as the lineal descendant of candidate Trump’s 2015 call for “a total and complete shutdown of Muslims entering the United States”? Additional statements by Trump both as a candidate and since becoming president provide powerful evidence that Ban 1.0 was an attempt to dress up Trump’s Muslim ban in legal garb and that each successive effort has been more of the same.

Perhaps a different administration might have conducted a global review of screening procedures and ended up with more or less the same policy that is contained in Ban 3.0, but as a matter of law that is not necessarily decisive.

A policy that has a disparate impact based on an illicit motive (such as racial or religious prejudice) is presumptively invalid, even though the same policy would be valid in the absence of the illicit motive.

Assuming that the courts do take account of Trump’s illicit motives for the travel ban, they might nonetheless uphold it if there is a very strong national security justification. The proclamation recites such a justification, but a recitation is not evidence.

The key question going forward may therefore be this: Will the courts require the government to provide evidence (potentially under seal to protect national security) that shows that Ban 3.0—despite its tainted origins—actually is vital to national security?

We will find out shortly whether that question will be answered in the first instance by the Supreme Court or a lower court, but before this saga is truly over, it will be answered somewhere.

Hoda Muthana's father, Ahmed Ali Muthana, filed the lawsuit in Washington D.C., and "seeks injunctive relief preventing the United States government from unconstitutionally robbing (Muthana and her son) of their rights as United States citizens."

"The ice doesn’t care what this administration thinks. It’s just going to keep melting," David Titley, the director of the Center for Solutions to Weather and Climate Risk at Penn State, told Newsweek.